US2795127A

US2795127A - Automobile door locking and unlocking means

Info

Publication number: US2795127A
Application number: US460034A
Authority: US
Inventors: Alex A Gust
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-10-04
Filing date: 1954-10-04
Publication date: 1957-06-11
Anticipated expiration: 1974-06-11

Description

AUTOMOBILE DOOR LOCKING AND umocxmc MEANS 1 A. A. GUST June 11, 1957 2 Sheets-Sheet 1.

Filed 001.. 4,

z u m m m m m m 2 flfi w w 6 f a INVENTOR. (Z6014 GM 3W, ;2,,BM $73M June 11, 1957 A. A. GUST AUTOMOBILE DOOR LOCKING AND UNLOCKING MEANS 2 Sheets-Sheet 2 Filed Oct. 4. 1954 INVENTOR. Q ZW Q 1246M, 3% $94M United States Patent AUTOMOBILE DOOR LOCKING AND UNLOCKING MEANS Alex A. Gust, Waukeg'an, Ill.

Application October 4, 1954, Serial No. 460,034

9 Claims. (Cl. 70-464) The present invention relates to means for automatically locking and unlocking'a plurality of locks from a single control station, and particularly, to means for automatically locking and unlocking all of the doors of an automotive vehicle by the simple expedient of locking and unlocking one door.

I am aware that certain proposals have been made heretofore in regard to means of the general character defined, but in such proposals, the door latching means as well as the ineans for barring or locking the latch were intended to be automatically actuated, which, of course, presents substantial problems with respect to the power required to unlatc'h the door and the great expense involved in endeavoring to provide all of the necessary 'instru-meutalities, and to provide instrumentalit-ies of the requisite power. Because of these and other problems and disadvantages inherent in the prior proposals in the art, automatic door locking and unlocking means of the character referred to have failed to attain practicality and have not been commercially acceptable.

it is an object of the present invention to provide improved door locking and unlocking means of a commercially practical and highly economical nature.

In distinction to the prior endeavors in the art, the present invention is not concerned with the provision of means forautomatically latching and unlatching doors, but, instead, has for its object the provision of means for rendering the door unlatching means operative and inoperative, thus to accommodate and prevent, respectively, openingof the doors, the operativeness and inoperativeness of all of the vehicle doors being controlled from a single door.

According 'to the invention, I provide, for example in a four-door passenger vehicle, three of the doors with controllable f'r'neans accommodating or preventing actuation of the door unlatching means, and the fourth door with the control means for the other three. In an automotive vehicle equipped with a storage battery, the most convenient and economical power for elfeoting control functions is electrical power derived from the battery, particularly since utilization of electrical power does not require that the vehicle "engine be in operation. 'In the preferred embodiments of my invention, the said conthe vehicle battery, when the door is unlocked and locked. The other three doors each include a lock bolt for barringthe door latching means, a solenoid operable to release'the lock bolt, and a normally open switch for ice , handle is initially operated, the switch associated there with is closed to energize the solenoid to release the lock bolt, whereupon the door may be unlatched manually by continued movement of the handle. However, if the front right hand door were locked, the solenoid could not be energized, and the lock bolt would prevent unlatching and opening of the door. a f

The structure defined affords the particular advantages that it does not in any way interfere with opening of the doors from the inside of the vehicle, at least one door can be opened, by means of the key, from the outside of the vehicle even if there is a power failure, door latching and iinlatching is eifected entirely conventionally, and there is no need to close the ignition circuit, operate the vehicle engine, or otherwise control door operation from the operators position at the steering wheel of the vehicle. All of the vehicle doors, when closed, are automatically locked when the right hand front door is locked, and are all rendered operable upon unlocking of that single door.

In addition to the foregoing, it is an object of the invention to provide an improved door locking and unlocking means of the character described of a simple, compact, inexpensive and efficient nature, wherein the said switches, solenoids and lock bolts, due to the compact ness thereof, are incorporated directly in the respective door handle.

A further object of "the invention is the provision of improved means of the character above defined, wherein the said switches, solenoids and lock bolts may readily and conveniently be installed in the existing handles and door structures of vehicles.

As will be appreciated, the accomplishment of said objects affords the advantages of particular economy and commercial practicality, and facilitates the even more c'oiuienient use and operation of modern vehicles.

Other objects and'advantages of the present invention will becomeapparent in the following detailed description of a preferred embodiment of the invention.

Now, in order to acquaint those skilled in the art with the manner of making, installing and using the door lockingfand unlocking means of the invention, I shall describe, in connection with the accompanying drawings, a preferred embodiment of the invention and a preferred mode of constructing the same.

In the drawings, wherein like reference numerals in- 'dicate like parts;

Figure 1 is "a somewhat schematic circuit diagram of the electrical arrangement provided according 'to the invention to accommodate automatic unlocking and lockin'g'ofthe four doors of a vehicle through the instrumentality of a-single door lock;

"Figure 2 is a bottom view, partly in plan and partly in "section, of a vehicle door handle equipped with the master control instrumentalit-y of the invention, a portion "of the vehicle door and door latching means beingshown "in dotted lines;

Figure 3 is a fragmentary horizontalsection of a'doo'r handle equipped with controllable means provided according to the invention for--automatically rendering the door unlatching means operative and inoperative;

.Figure 4 is a fragmentary sectional view taken substantially onthe line -44 of Figure 3; and

26 fitting and secured within the door structure.

being electrically connected to one terminal of the battery,

and the other battery terminal being grounded, as is conyentional; The switch is incorporated in one door of the vehicle, preferably, in the manner shown in Figure 2 and to be described indetail hereinafter. The other three and a solenoid 16, the switch and solenoid in each door being electrically connected in series with one another and, as a unit, being connected in series with, the master switch unit or :assembly is preferably incorporated in a door handle in the manner shown in Figures 3 to 5, to be de-,

scribed hereinafter. As will be appreciated from the .circuit diagram, closing of the switch 10 will not directly ing and unlocking of all of the doors automatically and simultaneously, as will appear more fully hereinafte'n Referring now to Figure 2, one vehicle door and handle are shown within which a preferred embodiment of the master switch 10 is incorporated. The door shown in Figure 2 preferably comprises the right hand front door of the vehicle, butmay, if desired, comprise any door of the vehicle. The door handle illustrated, indicated generally at 20, is of a type employed extensively in the automotive industry at this time and is substantially conventional. The handle 20 includes a hand grip portion 22, spaced from the outer surface of the vehicle door, shown in dotted lines and indicated at24, which portion of the handle terminates at one end, its rearward end, in a stud At its opposite or forward end, the handle includes a tubular portion 28.having areduced extension 30 also fitted and held within the door structure. The stud 26 and extension 30 retain the handle fixed on the door against relative movement, and the door latch is-adapted to be actuated bymeans of a push button 32 reciprocable in the tubular portion 28 of the handle. The push button is operatively associated with a rectangular rod or plunger 34 which extendsinto the door latch mechanism, outlined in dotted lines and indicated generally at 36, (to actuate the door latch 38, also shown in dotted lines. The latch mechanism does not form part of the present invention and the same is publicly known. Sufiice it to say that, with .the door unlocked, inward movement of the push button 32 effects withdrawal of the latch 38 to accommodate opening of the door upon exertion of anoutward pull on the hand grip 22. A lock of a conventional and known nature, forming no direct partof this invention, is incorporated in the conventional manner in the push button 32, the lock being provided with a key 40to facilitate locking and unlocking of the door from the exterior of,

maybe opened at any time, in an entirely conventional manner, even if there is a failure of electric power supply.

doors of the vehicleare each equipped with a switch 14 1 '10 individually or separately of the'other switches 14 and solenoids 16 of the circuit. Each'switch and solenoid To incorporate the master switch'10 in the handle 20, I prefer to mount the same directly within the tubular portion 28 of the handle and to actuate the switch in accordance with the rotary movement imparted to the lock, or the movable portion or bolt thereof, upon locking and unlocking of the door. By way of example, a preferred master switch 10 comprises a stationary cupshaped member 42 fitted into the tubular portion 28 of the handle and retained therein by means of a C-ring 44 or the like fitting within a circumferential groove in the inner wall of the tubular portion 28. Preferably, the cup-shaped member is formed of insulating material and includes a pair of diametrically opposed ears fitting within longitudinal grooves 46, conventionally provided in the inner wall of the handle portion 28, to retain the member 42 against rotation. The cup-shaped member is centrally apertured to accommodate passage of the plunger 34 and, to opposite sides of the plunger, carries a pair of 1 contacts 48, which are supported in insulated spaced relation by the member 42. The contacts 48 each comprise the terminals of electrical, conductors 50 which constitute, in effect, the lead from the battery 12 to the switch 10 and from the switch 10 to the switches 14 in the circuit diagram of Figure 1. Within the cup-shaped member 42, a second insulating member or disc 52 is rotatably mounted, the disc having a central opening complemental to the cross section of the rod 34, whereby the disc is rotatable with the rod. The disc 52 of insulation also carries a pair of contacts 54 and a conductor 56 extending between and electrically connecting the contacts. When the door is unlocked, as is shown in Figure 2, the contacts 54 engage the contacts 48, and the conductor 56closes the circuit between the conductors 50, thus to close the master switch 10. Upon locking of the door, the rod 134 and disc 52 are turned or rotated to such extent as to able switch. member or blade 52, 54 and 56 with the stationary contacts 48, a compression spring 58 is preferablyconfined between the push button 32 and the disc 52 to bias the disc into engagement with the contacts 48. Also, the spring 58 will normally serve to bias the push button to its outermost position, and to return the push button to such position after unlatching of the door.

The main switch 10 thus provided is of very simple and inexpensive construction and assembly, and the same is sufficiently compact to facilitate mounting thereof directly within the handle 20. Installation of the switch is rapidly and conveniently effected and requires no change 'in the handle.

Since the switch is only required to be closed when the door is unlocked and open. when the door is locked, it will be appreciated'that other switch forms may be employed with equal facility, and that other forms of switches may be required for difierent forms of latch operating means.

The mounting of controllable solenoid means according to the present invention in a switch handle is shown in a preferred embodiment in Figures 3 to 5. The door structure and the latching mechanism are .of the same character and structure shown in Figure 2 and described in conjunction therewith, and because of this identity, the door and latch are not indicated in Figure 3. Likewise, only a portion of the door handle 20 is shown, the handle including, as previously described, a hand grip 22, a tubular front portion 28 and extension 30 having longitudinal grooves 46" in the inner wall thereof, and a push button 32. The handle differs from that previously described in that the handle is not provided with a key lock and does not include the identical latch operating plunger above described. In this construction, the push button 32 has an imperforate outer end wall and is otherwise tubular, and is mounted for reciprocal movement within the tubular handle portion 28. A

solenoid coil 60 is mounted within the hollow interior of amatt the pushbutton, the same including a spool 62, formed of insulating material, upon which the wire of the coil is wrapped. Suitably, the spool 62 is retained within the push button, in engagement with the end wall thereof, by turning portions of the side wall of the button inwardly at the lower or inner end of the button, as is indicated at 64. At the upper end of the coil, one terminal of the coil wire extends through the spool to be grounded on the push button, as is indicated at '66. The other terminal of the coil wire, at the lower end of the coil, extends through the spool 62 and is electrically connected to a depending, elongate contact rod. The contact rod 68 is physically carried by the spool 62 and extends longitudinally downwardly 'or inwardly therefrom through the tubular portion 28 and extension 30 of the handle in spaced parallel relation to the axis of said portion. The spool 62 is tubular, or has a hollow core, within which a rod-like, magnetic armature 70 reciprocates, the armature being magnetically drawn upwardly into the spool core upon energization of the coil, and being biased downwardly and outwardly out of the spool core upon deenergization of the coil by means of a compression spring 72, which is confined between the push button 32 and the top surface of the armature.

To connect the push button 32 to the door latching mechanism, a tubular plunger 74 extends inwardly or downwardly from the push button toward the latch mechanism. The plunger 74 may be operatively connected in fixed relation to the push button in several ma'nn'e'rs. For example, I have shown a strong coil spring 76 retaining an end flange of the tube in engagement with the lower surface of the solenoid spool 62. Adjacent its inner or lower end, the tubular plunger 74 may suitably be provided with diametrically opposed slots 78 in the side walls thereof adapted for the reception of the di'ametrical tabs 80 of a plunger extension 82. The slot and tab association of the plunger 74 and its extension 82 accommodates axial offset of the plunger with respect to the latch mechanism, and also accommodates lengthwise adjustment of the plunger. In operation, when the push button 32 is depressed, the push button,

the solenoid coil and the plunger 74 are adapted to be moved inwardly toward the latch mechanism until the extension tabs Sil are engaged by the plunger at the end wall of the slot 78, whereupon the extension 82 is moved inwardly to effect the unl'a tching operation. To control such operation, the present inventionprovides a lock bolt in the handle cooperable with the tubular plunger 74. To accommodate such lock bolt, an inverted cup-shaped member 84, preferably formed of insulating material, is inserted in the lower end of the tubular extension 30 of the handle. The member 84 includes diametrically opposed ears 86 fitting within the longitudinal grooves 46 in the tubular portion of the handle to retain the member against rotation in the handle. The cup-shape of the member 84 defines a. chamber which is closed at its lower end by means of a disc 88, also preferably formed of insulating material, which is fitted and retained against rotation in the handle in the same manner as the member 84. A C ring 90' or the like seating within a circumferential groove in; the inner wall of the extension 30 normally retains the

members

84 and 88 in the handle. These members are provided with aligned bores adjacent one edge thereof accommodating passage therethrough of the contact rod". 68. Likewise, the members are centrally apertured to accommodate passage of the tubular plunger 74, the disc 88 preferably including an axial sleeve 92 surrounding the plunger '74. This sleeve affords a particular con-- venient mounting for a stationary contact, in that the: sleeve is provided with a circumferential groove therein adapted to receive agenerally -C-shaped spring contact: clip 94 connected to the outer end of an electrical concluster 96. The conductor 96 comprises one lead from.

the main switch 10, and is a continuation of oneof the".

6 conductors '50 shown in Figure 2. The contact clip 94 includes free end portions projecting beyond the 'sleeve 92 and disposed in alignment with the contact rod 68, so that upon depression of the push button 32, the rod 68 engages the contact 94 to close (if the main switch 10 is closed) the electrical circuit through the solenoid coil 60.

As thus confined within the handle, the member 84 affords a fixed support or base wall against which the spring 76 may bear to "retain the tubular plunger 74 in operative engagement with the push button, and also to retain the push button normally in its outermost position.

Within the chamber defined by the member 84 and disc 88, a lock bolt or obstruction block 98 is mounted for sliding movement transversely of the tubular plunger 74. As shown in Figure 5, the lock bolt comprises a generally U-shaped member straddling the plunger 74. A leaf spring 100 is embedded at one of its ends in the lock bolt and at its other end engages the wall of the member 84 normally to bias the lock bolt radially inwardly toward the plunger. At the portion thereof normally received within the chamber in the cup-shaped member 84 and sleeve 92, the side wall portion of the tubular plunger facing the bight portion of the U-shaped lock bolt 98 is cut away, as shown in Figures 3 and 4, to define a right angle abutment edge 102 at the upper or outer end of the cut-away portion, and an inclined surface 104 adjacent the lower end thereof leading into and inwardly or downwardly extending slot 106 in the side 'wall of the tube. The spring 100 normally biases the bight portion of the lock bolt 98 into the cut-away portion of the tube, so that upon partial depression of the push button, the abutment edge 102 of-the plunger 74 normally engages the lock bolt 98 to prevjent inward movement of the plunger and unlatching of the door. Such slight inward movement of the plunger is accommodated without resulting in unlatching of the door by the slot and tab connection of the plunger 74 and its extension '82.

To effect release of the plunger 74, and thus to accorn'modate unlatching of the'door, the solenoid armature 70 comprises an elongated solid rod extending through and guided by the tubular plunger 74. At the cut-away portion of the tube 74, the armature rod 70 is similarly cut away, that is, in the portion thereof normally coextensive with the cut-away'portion of the tube 74, to define :a right angle abutment edge 108 at the upper end of the cut-away and an inclined cam surface 110 at the lower end of the cut-away. Instead of being slotted, the rod '70, immediately below the cam surface 110 thereof, includes a radially outwardly extending projection 112 which is normally received within the slot 106 in the tube 74 and which includes a surface 114 constituting a continuation of the cam surface 110. The armature 70 is thus held against rotation with respect to the plunger 74 and :obstruction block or lock bolt 98 by the projection 112 acting within the cut-away portion and slot 106 of the plunger. The cam surfaces 110 and 114 of the armature 70 are adapted to engage the lock bolt 98, and the lock bolt may suitably be provided with a complemental cam :su'rface 116 at the inner lower edge of'the bight portion thereof.

Assuming the main switch 10 is closed, i e., that the from right hand door of the vehicle is unlocked, whether e'the vehicle door be opened or closed, opening of another vehicle door is accomplished as follows: the push button 32 is pressed inwardly to move the coil 60, contact rod 68 and plunger 74 inwardly, such inward move- :ment being accommodated by clearance between the abutment edge 102 of the plunger and the lock bolt 98. Such movement as is accommodated by the "said clearance results in thelower or inner end of the contact rod 68 being moved into engagement with the contact clip 94, whereupon the electrical circuit is closed from the battery .12 through the switch 10, conductors 50 and 96, clip 94, rod 68 and coil 60 of the solenoidto ground, to energize the solenoid. When the coil of the solenoid is energized, the armature 70 is magnetically pulled into the coil, thus moving the cam surfaces 110 and 114 on the armature upwardly or outwardly toward the lock bolt 98. As the cam surface 110 engages the cam surface 116 of the lock bolt, the lock bolt is moved radially outward against the bias of the spring 100, and such movement continues as the cam surfaces 110 and 114 progress upwardly, thus to move the bight portion of the lock bolt out of the cut-away portion and out of the path of the plunger 74. 1 The upward movement of the armature is limited by engagement of the projection 112 .with 'the abutment edge 102 of the plunger 74, whereby the armature and its projection prevent reentry of the lock, boltinto the cut-away portion of the plunger while the solenoidis energized. With the lock bolt 98 thus released, further inward movement of the push button and plunger is accommodated. During such movement, the solenoid coil and armature are moved inwardly with the plunger to clear the lock. bolt 98, whereafter the lock bolt rides. on the imperforate surface of the plunger outwardly of the cut-away portions thereof, such inward movement resulting in compression of the spring 76.

V Also, during the further or continued inward movement of the plunger, the contact rod 68 is moved downwardly or inwardly, and to accommodate this movement, the contact clip 94 includes flexible or resilient end portions through which the contact rod may pass. The contact rod may be exposed or bare throughout its length -to be engaged by the clip 94 to maintain the solenoid energized during the entirety of door unlatching movement of the handle. However, because of the tendency of users to hold the push button in or depressed a longer length of time than is required and to minimize energization of the solenoid, and to eliminate unnecessary energization of the solenoid, I prefer to insulate all but a small end portion of the rod 68 by means of an insulating tube 118. The exposed end portion of the contact rod 68 is of a length to insure energization of the solenoid during the portion of movement required to disposed the imperforate portion above the edge 192 of the plunger 74 in alignment with the lock bolt 98, whereafter the solenoid may be deenergized by disposing the insulation 118 between the contact rod 68 and the contact clip 94. Upon deenergization of the coil 60, the spring 72 moves .the armature 70 inwardly of the plunger 74 to dispose the projection 112 in the bottom of the slot 106.

Upon continued inward movement of the push button I 32 and plunger .74, the end wall portions. of the plunger 74 bounding the slot 78 therein engage the tabs 80 of the plunger extension 82 to move the extension inwardly to effect unlatching of the door in a conventional manner. A pull may then be exerted on the hand grip 22 to open the door, whereupon the push button 32 may be released. As the push button ,is released, the spring 76 returns the push button "32, coil 60, contact rod 68, armature 70 and plunger 74 outwardly or upwardly to release the extension 82 and the door latch. Adjacent the end of spring effected movement, the solenoid may be instantaneously energized by passage of the. exposed end of the contact rod 68 through the clip 94, but such energization is of such short duration as to impart no appreciable movement to the armature 70, and even if it did, no harm would be done. Also adjacent the end of spring effected movement, the abutment edge 102 of the plunger 74 clears the lock bolt 98, whereupon the lock bolt is returned to its plunger blocking position by the spring 100. Thereafter, if the main switch remains closed, the other doors may be opened at any time in the manner described, ..but if the main switch 10 is opened, by locking the right hand front door of the vehicle, the lock bolt 98 will prevent operation of the latches of the other doors.

preferred embodiment of the invention are simple, inexpensive and compact, so compact in fact as to be mounted directly within the respective door handle. Further, the construction is such that the means of the invention may conveniently and economically be installed in existing door handles without modification or reconstruction of the handles. Specifically, with either of the structures shownin Figures 2 and 3, the components of the apparatus of the invention are inserted in the handle in the order indicated, whereafter the components are secured within the respective handle by means of the C-

rings

44 and 92. In the structure of Figure 2, the conductors are quickly united to the contacts 48 in a conventional manner. In the structure of Figure 3, the contact clip 94 and conductor 96 are readily associated with the apparatus merely by slipping the contact clip over the sleeve 92 and fitting the same within the circumferential groove in the sleeve. Further, the electrical wiring re quired is of the simplest nature and is readily installed in known manners by anyone acquainted in the art.

In addition to the above, the present invention affords automatic, door locking and unlocking means that in no way interfere with the conventional and intended operation of the vehicle doors. The doors may be opened from the interior of the vehicle in an entirely conventional manner. The door in which the master switch is incorporated is operated entirely manually, and does not rely onany electrical energization. Should the battery of the vehicle go dead, this door may still be opened from the exterior of the vehicle, and the remainder of the doors, though locked from the outside, may be opened from the interior of the vehicle. Also, all doors may be closed at any time, whether the main switch is open or closed, since the means and apparatus of the invention do not block the door latch per se. The invention has been described principally with respect to the doors of a four-door passenger vehicle, but it is to be appreciated that the invention is equally applicable to two or more doors in any vehicle, to two-door vehicles, and ,to the passenger and cargo doors of commercial vehicles.

With respect to the power requirements of the solenoid control means, it is to be observed that the lock bolt 98 is a particularly small member and that the only force resisting movement thereof is the leaf spring 100, which need not be a particularly strong spring. Secondly, the cam surfaces 110 and 114 provided on the solenoid armature 70, and the cam surface 116 provided on the lock, bolt, afford a substantial mechanical advantage in moving the lock. bolt laterially of the tubular plunger 74. In view'of these considerations, it is to be appreciated that the solenoid coil need not set up a particularly powerful magnetic field. Further, since the handle 20 is normally located in a horizontal plane, the armature of the solenoid is also disposed horizontally, so that the solenoid coil is not required to lift a weight, thus further minimizing the power requirement of the solenoid coil. In addition, in the preferred embodiment, the solenoid is only energized momentarily, i. e., sufficiently to move the armature to the extent necessary to move the projection 112 into engagement with the abutment edge 102 of the plunger. Accordingly, it is to be appreciated that the power requirements of the solenoid coil are only momentary for each opening of the door and that the power requirement is quite low.

While I have described what I regard to be a preferred embodiment of my invention, it is to be appreciated that various changes, rearrangements and modifications may be made therein without departing from the scope of the invention, as defined by the appended claims.

I claim:

1. Means for simultaneously locking and unlocking a plurality of doors, one of the doors comprising a :master door and having a latch, a handle for operating the latch and a lock for locking and unlocking the .door, the other doors each having a latch and a handle for operating the latch, said means comprising, a combination, a single master control in the master door, said master control constituting the sole instrumentality of said means in said master door, and controlled energizable means in each of the other doors interposed between the handle and the latch of the respective door, said controlled energizable means when not energized preventing and when energized accommodating unlatching of the respective door latch by the respective handle, said master control being connected in series with a source of power and with each of said controlled energizable means, said master control bein operatively associated with the lock in the master door to accommodate release of power to each of said controlled energizable means when the master door is unlocked and to prevent the su ply of power to each of said controlled energizable means when the master door is locked.

2. Means for simultaneously locking and unlocking a plurality of doors, one of the doors comprising a master door and having a latch, a handle for operating the latch and a lock for locking and unlocking the door, the other doors each having a latch and a handle for operating the latch, said means comprising, in combination, a single manually operated master control in the master door, said master control constituting the sole instrumentality of said means in said master door, and controlled energizable means in each of the other doors interposed between the handle and the latch of the respective door, said controlled energizable means when not energized preventing and when energized accommodating unlatching of the respective door latch by the respective handle, said master control being connected in series with a source of power and with each of said controlled energizable means, said master control being operatively associated with the lock in the master door to accommodate release of power to each of said controlled energizable means when the master door is unlocked and to prevent the supply of power to each of said controlled energizable means when the master door is locked, each of said controlled energizable means including a secondary control in the respective door in series with the source of power and said master control, said secondary controls each being operatively associated with the handle of the respective door to be operated upon door unlatching v movement of the respective handle to release power to, when the master control accommodates release of power, and energize the respective controlled energizable means to accommodate unlatching and opening of the respective door by the respective handle.

3. Means for simultaneously locking and unlocking a plurality of doors each having a latch and a handle for operating the latch, only one of said doors having a lock for locking and unlocking the same, said means consisting of a single manually operated master switch to be disposed in the said one door and operatively associated with the lock thereof to be open when the said one door is locked and closed when the said one door is unlocked, a normally open secondary switch to be disposed in each of the other doors and operatively associated with the handle thereof to be closed upon door unlatching movement of the respective handle, and electrically energized means to be disposed in each of the said other doors operatively between the latch and the handle of the respective door, each of said electrically energized means to be disposed normally to prevent operation of the respective latch by the respective handle and, upon energization, to accommodate operation of the respective latch by the respective handle, the secondary switch and the said electrically energized means in each of the said other doors to be connected in series and to be connected as a unit in series with said master switch and a source of electric power individually of the secondary switch and electrically energized means in the other ones of the said other doors.

4. Means for simultaneously locking and unlocking a plurality of doors each having a latch and a handle for operating the latch, only one of said doors having a lock for locking and unlocking the same, said means comprising a master switch to de disposed in the said one door and operatively associated with the lock thereof to be open when the said one door is locked and closed when the said one door is unlocked, said master switch constituting the sole instrumentality of said means in said one door, a normally open secondary switch to be disposed in each of the other doors and operatively associated with the handle thereof to be closed upon door unlatching movement of the respective handle, a solenoid to be disposed in each of the said other doors, and a lock bolt to be disposed in each of the said other doors operatively between the latch and the handle of the respective door normally to prevent operation of the respective latch by the respective handle, the secondary switch and solenoid in each of the said other doors to be connected in series with one another and to be connected in series as a unit with said master switch and a source of electric power individually of the secondary switch and solenoid in the other ones of the said other doors, each of said solenoids to be operatively associated with the lock bolt in the respective door to move, upon energization thereof, the respective lock bolt to accommodate operation of the respective latch by the respective handle.

5. In a door having a latch and handle assembly including a push button for operating the latch, a tubular plunger extending between the push button and the latch operatively to connect the same, said plunger having a cut away portion defining an abutment edge to the side thereof adjacent the push button, a laterally movable lock bolt mounted in the handle and normally extending into said cut-away portion to be engaged 'by said abutment edge to prevent movement of said plunger by the push button thus to prevent operation of the latch, a solenoid coil on said plunger between the push button and said cut-away portion, and a solenoid armature reciprocable in said plunger to be moved toward the push button upon energization of said coil, said armature including a cam surface to the side of said lock bolt away from the push button and facing toward said lock bolt and the push button, said cam surface being cooperable with said lock bolt upon energiz' tion of said coil to move said lock bolt laterally outward of said abutment edge to release said plunger to accommodate operation of the latch by the push button.

6. Door locking and unlocking means for a first door having a latch, a handle for operating said latch and a lock for locking and unlocking the door, and a second door having a latch and a handle for operating said latch, said means comprising a switch in said first'door operatively associated with said lock to be closed when said door is unlocked and open when said door is locked, said switch comprising the sole instrumentality of said means in said first door, a lock bolt in said second door normally preventing unlatching of the latch of said second door by the handle thereof, a solenoid in said second door operatively associated with said lock bolt to release said lock bolt when energized, and a normally open switch in said second door operatively associated with the handle thereof to be closed during door unlatching movement of said handle, said solenoid and said switches being connected in series with an electric power source.

7. A handle for actuating a door latch comprising a manually operable member to be operatively associated with the latch, a lock bolt in the handle operatively related to said member and normally preventing operation of the latch by said member, electro-magnetic means mounted in the handle concentric with said member, said electromagnetic means being operatively associated with said lock bolt to eflect retraction ofisaid lock bolt when energized, said lock bolt when retracted accommodating actuation of thelatch by said member, and a normally open switch'in the handle in series with said electromagnetic means, said switch including a stationary contact mounted in the handle and a movable contact carried by said member, said movable contact being moved by said member toward engagement with said stationary contact upon movement of said member to actuate the latch.

8.In a handle for a door latch, a generally tubular housing, a hollow member movably mounted in said housing concentric therewith for actuating the door latch, an t electromagnetic coil mounted concentrically in said memher, and a lock bolt in said housing operatively related to said member and the normally preventing actuation of the latch by said member, said electro-magnetic coil being operatively associated with said lock bolt to effect retraction of said lock bolt upon energization of said coil to accommodate operation of the latch by said member.

9. In a handle for a door latch, a generally tubular housing, a hollow member movably mounted in' said housing concentric therewith for actuating the door latch, a solenoid coil mounted concentrically in said member, a solenoid armature slidably mounted in said coil concentrically therewith, and a lock bolt insaid housing movable generallyrtransversely of said armature, said lock bolt normallytbeing disposed in the path of movement of said member normally to prevent actuation of the latch by said member, said armature being operatively associated with said lock bolt to effect retraction of said lock bolt upon energization of said coil to accommodate operation of the latch by said member.

References Cited in the file of this patent UNITED STATES PATENTS 2,006,624 Block July 2, 1935 2,329,309 Ward Sept. 14, 1943 2,371,370 Ward Mar. 13, 1945 2,466,481 Royal Apr. 5, 1949